The role of Core B, the Informatics and Expression Core (IEC) is multifold and serves to provide resources and perform for the investigators and/or the projects in order to accomplish research objectives in a timely and cost efficient manner. A major activity of the IEC will be the construction and analysis of cDNA arrays for large-scale library screening and transcript expression studies. We are well positioned to provide this resource by virtue of our efforts to develop and prostate-centric gene expression orientation with the following resources: 1. Development of an informatics resource termed the Prostate Expression Database (PEDB). 2. Production and assembly of Expressed Sequence Tags (ESTs) for gene identification exclusively from prostate tissues. 3. Production and archiving cDNA libraries and sets of cDNA clones derived from a wide variety of normal and neoplastic prostate tissue components. 4. Development and Application of cDNA Expression Array Technology to prostate carcinogenesis. The IEC will also provide software and hardware support for investigators performing sequence homology comparison algorithms and using other sequence analysis tools, and will serve as a sequence retrieval service to provide specific cDNA and genomic clones to Project investigators for bench experiments. Finally, the IEC will provide a high quality and rapid turn-around DNA sequencing support service to facilitate 1) the identification of cDNA clones identified by investigators as interesting by virtue of differential expression or library screening 2) the validation of expression construct assemblies and 3) Expressed Sequence Tag (EST) production from tissue type and cell-type specific cDNA libraries.